I had a mosquito ringtone on my mobile. Used to drive the cat crackers..

Slightly off-topic, but some places play classical music really loudly to disperse 'yoofs'. West Croydon bus station and Clapham Common tube spring to mind. The BBC covered it a few years ago, apparently the Co-Op were trying it in their stores

And E&C (Bakerloo Line), at least on some mornings - although it is proper music recordings, rather than "musak" (i.e. the real thing rather than some atrocious pan-pipe rendition). I think its great. It cheers me up. I hope it cheers the staff up!